Combine dandelion petals and 4 cups of water in the saucepot. Bring to a boil over high heat, stirring occasionally. Boil for 1 minute. This will be the dandelion "tea".
Remove the tea from the heat, let cool down to room temperature. Cover and refrigerate for 12-24 hours.
After the tea has steeped for 12-24 hours, strain the petals using a fine mesh colander or cheesecloth. Use the back of a spatula to press on the petals or your hand if using the cheesecloth. Get as much of the liquid out as you can.
Set the tea aside, discarding the petals.
Fill large stockpot with water, enough to cover the jars by an inch or two. Bring it to a boil over high heat. Carefully dip canning jars and rings into the water, let simmer about 5 minutes. Then dip the canning lids in for about 1 minute. Remove all, set aside on towels. Cover the pot and reduce the heat to a simmer while the jelly is being made.
While the canning water comes to a boil, in the medium saucepot combine the strained dandelion tea, packet of pectin and lemon juice. Bring to a boil over medium high heat, stirring occasionally.
Once the tea begins to boil, add the sugar. Stirring frequently, bring this to a boil that cannot be stirred down. Once it hits that stage, boil for 1-2 minutes. Then remove from heat.
Skim any foam from the top. This can be easier if you let the jelly sit for a few minutes.
Carefully ladle the hot jelly into each jar.
Wipe each rim with a fresh, damp kitchen rag or paper towel.
Place a fresh lid on each jar, followed by a ring. Tighten only slightly, enough to keep the lids in place.
Using jar lifter, place the jars in the large stockpot.
Turn the burner to high, bring water to a boil.
Cover and boil for 5 minutes for jelly jars, 10 minutes for pints.
Remove from the water, set aside on a towel and do not disturb for 24 hours.
After the 24 hours, check the seals on the lids. Refrigerate any unsealed jars and use within a month. Sealed jars should last at least 12-24 months.